Just for information
In fact the Rhesus is a system containing many type
+ or - refer to D you have it or not
There is also C, c, E, e...etc
Same goes to ABO
Anyone heard of Duffy, Kell...
There is also Bombay (H) in ABO which isn't A nor B nor O even if it shows you as O type.
I love the O- he loves everybody but nobody loves him
Edit : normally we should obtain O>A>B>AB